Chapter 10 Plant Anatomy & Physiology Michael G. Simpson Study of tissue and cell structure of plants. (In zoology, anatomy is study of internal organs; histology is study of tissues/cells.) Plant Physiology Study of metabolic processes in plants.

Cell Theory All of life is composed of 1 or more cells. Cells arise only from pre-existing cells, via cell division or cell fusion. Cells are units of metabolic processes. Each cell contains set of hereditary information (DNA), transferred from cell to cell, coding for structural & functional features.

ribosomes: site of protein synthesis storage high energy carbs. transport & modification storage: pigments, acids, ergastic substances contains DNA structural support respiration cell recognition, transport photosynthesis protein synthesis & transport of materials ribosomes: site of protein synthesis

Ergastic Substances: not actively metabolized (storage/waste) aleurone grains: protein Ergastic Substances: not actively metabolized (storage/waste) oil bodies amyloplasts (starch grains): alpha-1,4-glucopyranoside chromoplasts druses raphides styloids prismatics crystals (Ca-oxalate; silica)

mainly cellulose: beta-1,4-glucopyranoside cell wall mainly cellulose: beta-1,4-glucopyranoside

lignin - secondary cell wall function?

Cell differentiation: 1) Cell expansion (elongation) meristem - region of actively dividing cells 1) apical (shoot & root); 2) lateral (vascular & cork cambia) Cell differentiation: 1) Cell expansion (elongation) 2) Cell maturation / specialization

Plant Tissues & Cell Types = group of cells with common function or structure. Three broad tissue types: 1) Dermal - outside layer(s) 2) Vascular - conduction 3) Ground - between dermal and vascular Simple vs. Complex Tissue: 1 versus 2 or more cell types

Ground Tissue Parenchyma: Gen. metabol. 1) Isodiametric to elongate 2) Primary cell wall 3) Living Collenchyma: support 1) Elongate 2) Primary cell wall thick, uneven, rich in pectins 3) Living

Ground Tissue Sclerenchyma 1) Secondary cell wall (+ primary) 2) Dead at maturity (usually) Fibers Elongate, sharply tapering

Ground Tissue Sclerenchyma 1) Secondary cell wall (+ primary) 2) Dead at maturity (usually) Sclereids Isodiametric to irregular

Vascular Tissue Xylem Water & mineral conduction Tracheary elements + parenchyma + sclerenchyma Phloem Sugar conduction Sieve members + parenchyma + sclerenchyma - Both complex tissues

Tracheary Elements Tracheids - Imperforate Vessels - Perforate Angiosperms (most) Gnetales A few Monilophytes

Sieve Elements Sieve cells - No sieve plates Sieve tube members - Sieve plates Apomorphy of Angiosperms

Dermal & Secretory tissues & cells Epidermis Glands Stomates Nectaries Laticifers

Dermal tissues: Trichome anatomy Epidermis

ROOT (l.s.) Protective root cap Absorptive root hairs root apical meristem ROOT (l.s.) Protective root cap Absorptive root hairs

3) Give rise to new roots endogenously (from within) ROOT (c.s.) 3) Give rise to new roots endogenously (from within)

Casparian Strip Function: forces fluids from outside through plasma membrane = selective absorption

SPOROPHYTIC SHOOT

Stems: Give rise to leaves exogenously Do not have a protective “cap” of cells Do not have root hairs (but may have trichomes)

Stelar types eustele atactostele

Protoxylem maturation

Vascular cambium - a lateral meristem

Conifers: non-porous

Ring porous Diffuse porous

Wood Ray Anatomy

Leaf anatomy

Stomata

C3 Photosynthesis

Kranz anatomy

C4 Photosynthesis

CAM photosynthesis